oracle-mcp

MCP server for Oracle Database: one server, many named connections. Built on the official node-oracledb driver in thin mode, so the Oracle Instant Client is not needed.

Tools

Every tool takes an optional connection argument. If you leave it out, the server uses default from the config file.

* The write tools are listed when at least one connection has "allowWrite": true. They are refused on connections that don't have it.

Related MCP server: Oracle DB MCP Server

Configuration: connections.json

The server reads connections.json next to index.js. To use another file, set ORACLE_CONNECTIONS_FILE. The file is git-ignored; connections.example.json is a template.

{
  "default": "app-uat",
  "connections": {
    "app-uat": {
      "appsettings": "C:/repos/MyApp/Api/appsettings.Development.json",
      "connName": "DefaultConnection",
      "allowWrite": true
    },
    "app-prod-ro": {
      "user": "APP_READER", "password": "***", "connectString": "db-host:1521/ORCLPDB1"
    }
  }
}

• appsettings + connName: the server reads the .NET connection string (User Id=..;Password=..;Data Source=host:port/service) from that file when it connects. The password never leaves the file where it already lives. JSONC comments are tolerated.

• user / password / connectString: inline credentials.

• allowWrite defaults to false.

Legacy mode: if there is no config file, the server builds a single default connection from these env vars:

• ORACLE_APPSETTINGS + ORACLE_CONN_NAME, or ORACLE_USER / ORACLE_PASSWORD / ORACLE_CONNECT_STRING

• ORACLE_ALLOW_WRITE

Install

npm install
cp connections.example.json connections.json   # then edit
claude mcp add oracle -s user -- node /path/to/oracle-mcp/index.js

To add a database later, edit connections.json and restart the session. You don't need to re-register the server.

Requires Node.js 18+.

License

MIT, see LICENSE.